Abstract: A dry-type transformer having an iron core, with high voltage and low voltage coils encapsulated in casting resin. The high and low voltage windings may be cast separately, or together. Either or both of the coils may have integral axial cooling channels, as may the annular axial space between the inner and outer windings (usually low voltage and high voltage, respectively). Coil cross-section is a modified oval (Rectoval.TM.) shape, in that the sides of the coil are substantially linear and the ends of the coils are substantially semi-circular. The aspect ratio (L/W) of the coil, when viewed in radial cross-section, ranges from greater than 1.0 to about 2.5. The rectangular nature of the coil allows for the use of a core member having a rectangular cross-section, thereby reducing the manufacturing expense involved with shaping the core member. The circular nature of the ends of the coil provide improved strength similar to that of circular/cylindrical coils.

Abstract: A conveyor belt system having an improved pulley is disclosed in which the improved pulley includes a roller having grooves of varying width machined into the cylindrical surface of the roller to form raised guides or lands of equal width therebetween which spiral outward relative to the center of the roller with decreasing pitch. The contacting surface of the guides is operative to engage a conveyor belt or webbing passing over the pulley and the varying pitch of the guides allows for the quick centering of unaligned belts or webs. The roller may be machined to have more than one helical guide spiralling outward from the center of the cylindrical surface of the roller at one time. The guides may be squared, chamfered or rounded and may optionally contain serrations. The roller may additionally be machined to taper slightly from its center to the respective ends thereof.